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United States Patent | 5,204,992 |
Carpenter | April 20, 1993 |
A battery discharge load current control system for a motor vehicle electrical system. The system has a short term timer and a long term timer. The timers are comprised of pulse counters that count constant frequency clock pulses. The short term timer will disconnect certain inadvertent loads from the battery after the elapse of a time period. Inadvertent loads as those that are controlled by a control switch that has not been turned-off by the driver of a vehicle. The long term timer disconnects parasitic loads from the battery after the elapse of a time period. Parasitic loads are those that are normally permanently connected to the battery. The time periods can be varied as a function of the number of miles that the vehicle has been driven and are increased after the vehicle has been driven a predetermined number of miles. The short term timer can be reset to start a new timing cycle if the control switch is closed after the short term timer has disconnected the inadvertent load from the battery.
Inventors: | Carpenter; James A. (Durand, MI) |
Assignee: | General Motors Corporation (Detroit, MI) |
Appl. No.: | 620467 |
Filed: | November 30, 1990 |
Current U.S. Class: | 307/10.7; 377/16; 377/107 |
Intern'l Class: | H02H 007/18 |
Field of Search: | 307/10.1,10.6,10.7,10.8,38,39,113,115,141.4,592,595,596,598,603 377/16,107,110 320/38,13 340/636 |
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